In order to provide a desired steering action on the steerable wheels of a toy car by operating its steering wheel, it is conventional practice to use steering devices which comprise essentially a steering column, to which the steering wheel is attached, arranged to act on a tie rod or crossbar of the steering system; the tie rod is in turn connected, as by means of links or steering arms, to two steering knuckles, a steerable wheel being associated with either knuckles. These prior steering devices usually employ such coupling arrangements as screw-and-nut, gear segment, or rack-and-pinion mechanisms for linking the steering column to the tie rod.
In general, the tie rod is, in common with the steering knuckles for the steerable wheels, steering arms and wheel axles, a part of the well-known articulated quadrilateral steering arrangement.
Such prior steering systems exhibit, however, the well-recognized drawbacks of a complex design and construction, and involve highly accurate designing and manufacturing procedures for their several members; all this reflects in costs which are objectionably high in view of the product for which they are intended, namely toy cars.
In an effort to obviate such drawbacks, a further type of steering device has been proposed which also conforms with the aforementioned articulated quadrilateral principle.
That further type, as disclosed in Italian Patent of Industrial Invention No. 1096250, for example, comprises a steering system tie rod which is formed with weakening lines effective to define two parallel hinges intervening to the end portions and the middle portion of the tie rod. Said end portions form, on bending, the aforementioned steering arms for connection to the steering knuckles. The steering column acts at some intermediate location on the middle portion of the tie rod, in between the weakening lines.
While advantageous in more than one way, not even this latter conventional type of steering device is devoid of such drawbacks as overall vulnerability as is evinced, especially after prolonged use, by the occurrence of breakage and deformation due to the stresses brought into play be the steering action on the steerable wheels concentrating at the very weakening lines, that is in areas which have been slenderized and whose construction has become inherently more fragile.
Still another drawback is, moreover, that the assembly procedure for such a conventional steering device involves an additional step, since the end portions of the tie rod must be properly bent relatively to the tie rod prior to assembling to the bodywork of the toy car.